Electronic distributor for counting and similar purposes



1956 P. F. M. GLOESS ET AL. ZWOAN ELECTRONIC DISTRIBUTOR FOR COUNTINGAND SIMILAR PURPOSES Filed June 9, 1949 5 Sheets-Sheet l INVENWMQ PAULFRANCOIS FARE GLOESS AND JEAN ARTHUR MLRIE LOUIS GALIAVARD NOV, 13, 1956p, F. M. GLOESS ET AL BJZQAN ELECTRONIC DISTRIBUTOR FOR COUNTING ANDSIMILAR PURPOSES Filed June 9, 1949 s Sheets-Sheet 2 47. U INVENIORS.PAUL FRANCOIS MARIE GLOESS AND JEAN ARTHUR LOUIS GALLAVARDJN I In. 131956 P. F. M. GLOESS ET AL 577M ELECTRONIC DISTRIBUTOR FOR COUNTING ANDSIMILAR PURPOSES Filed June 9, 1949 s Sheets-Sheet 5 PAUL FRANCOIS MARIEGLOESJ IKQ JEAN ARTHUR MARIE LOUIS QALLAVARDIN I ATTORNEY United StatesPatent ELECTRONIC DISTRIBUTOR FOR COUNTING AND SIJVHLAR PURPOSES PaulFrancois Marie Gloess and Jean Arthur Marie Louis Gallavardin, Paris,France Application June 9, 1949, Serial No. 98,146 Claims priority,application France July 7,1948: Claims. (Cl. 2.35--6-1) This. inventionrelates to'the distributionin space of electrical pulses arrivingsuccessively and more particularly to the counting of pulses succeedingat a high speed.

Up to the present time, the pulses were counted by means of apparatuscomprising vacuum or gas filledrelaytubes, and more particularly by;means of multivibrators. These apparatus are rather complicated and needa high number of tubes with numerous connexions; moreover, theygenerally count in a binary relation, and need supplementary devices totranslate the recordedtot-al into a more usual counting system, such asa. decimal one. These additional devices and their connexions complicatestill more the realization and introduce moreover substantially delaysreducing the counting speed.

It is well known at present to use commutating' or distributing devicesin the form of a cathode ray tube comprising a certain number of targetsdisposed generally in a circular relation, swept successively by an.electronic beam the movement of which is controlled by a rotatingdeflecting field. The pulses to be distributed can be either applied tothe beam, such as by its modulation, and collected on the targets, orthey inversely may be applied directly to the targets and thendistributed by the beam, introducing them in the anode supply circuit.In these devices, the deflecting field turns at a constant. speedindependent of the moment at which the pulses are ar riving, and theycannot therefore be used for counting purposes especially when thepulses are arriving irregularly, which is generally the case. On theother hand, in order to simplify the construction and the wiring, itwould be of a high interest to use such a tube for counting purposes,but it would then be necessary to secure first that the change of thebeam position from one target to another be controlled by the incomingpulses themselves, Whatever their arrival moment may be, and then thatthe beam remain in any new position, between the succeeding pulses or atthe end of the counting period. Moreover, it would be necessary that thedevice give at any instant an indication of the total number of pulsesrecorded by it.

This invention has for its principal object a pulse counting apparatus,using a. cathode ray tube of a simplified design, of a reduced volumeand working in a reliable manner.

The invention has also for its object a new type of cathode ray tubedistributor, in which the movement of the electronic beam is controlledby the pulses to be distributed on the different targets, moreparticularly for counting them.

The invention has also for its object a cathode ray distributor in whichthe movement of the beam is controlled step by step by the incomingpulses, and in which the beam keeps its position as long as it is notacted by a new pulse.

The invention has also for its object a cathode ray device whichindicates at any instant the number of pulses recorded by it, and moreparticularly a cathode ray tube the luminescent screen of which iscombined with a scale marking the counting results.

The inventionhas. also for its object a cathode ray tube distributorwhichcounts as well in the addition as in the subtraction senses andwhich more particularly can secure a differential counting effectresponsive to the sign of the applied pulses.

Still another object of this invention a counting systemcomprisingseveral cathode ray tube distributors connected in series in adecimal or other relation.

Other objects oi the invention will hereinafter appear.

According to the general idea of the invention, the cathode ray tube isgiven several targets arranged in a particular manner, and one makes useeither directly of the negative charge due to the electron impact or ofthe positive charge taken by the targets owing to their secondaryemission, for building up a deflection field which makes the beam glideon the target until it gets an equilibrium position and comes there to astandstill. The equilibrium of this servo-regulation is reached when thecharge of the target, with which is associated a. suitable leakagecircuit, becomes stationary.

in order to build up. these deflection fields designated in the presentspecification as regulating fields, the tube is provided with a certainnumber of deflecting means, preferably in the form of electrostaticallyacting plates, each of them deflecting the beam in a particulardirection and connected individually to its corresponding target.

To secure the commutation, e. the passage or" the beam from one targetto the other under the action of the incoming pulses, the apparatus isequipped with an additional means designated as a commutating element,which receives the incoming pulse and impresses onthe beam a suddensupplementary deflection, so that it leaves the equilibrium position onone target and gets to another one where it comes to a standstill owingto the above mentioned servo-regulation effect and so on.

This commutating element will be preferably given the form of anadditional electrode inside the tube, producing a supplementarycommutating field, superposed on the regulating field. This commutatingdeflection may also be secured through an action of the incoming pulseon the beam speed, such as by using this pulse to cliange suddenlybyallsuitable and welliknown means, the anode voltagefixing the beamacceleration.

The targets will be given a band form, and theywill be by preference,arranged as well as the regulating electrodes, in a circularrelationship around the tube axis, the regulation fields being thusdistributed in different radial planes extending through this axis. Onthe other hand, the targets will be mutually distributed so as to meetsuccessively in the same radial plane, at least two of them;

The commutation field will then be preferably secured by means of twocylindrical electrodes concentrically disposed respectively tothe tubeaxis and producing a radial field distributed uniformly round this axis.

According to one embodiment of this invention, the end portion of atarget, corresponding to an equilibrium position of thebe'am and the endportion, corresponding to an instable position, of the next target areput in the radial plane of the regulation electrode connected to thefirst. target.

' Accordingxto another embodiment intended for differential counting,the target-bands are overlapping each other, the radial plane of adeflecting plate cutting the central portionof target connected to it.

' Means for stabilization of potential will be associated with eachtarget and its regulation deflector, by preference in the form ofleakage resistances of a suitablevalue, connected to the anode supplycircuit of the tube. If secondary emissionproperty is used, thisconnection will be made through a suitable bias voltage source.

The starting or zero position of the beam will be secured by means of anaxially disposed target, connected to one of the distributing targets ormaking part of it. For connecting in series several tubes in order touse their scales in a determined, such as decimal, numerical relation,it would be only necessary to connect the last target of one of themwith the commutating element of the following tube. In order to securewith such system the differential counting, additional linking targetswill be introduced, as it will be described later.

According to still another embodiment, the electronic beam will be givena relatively large section and a slow acceleration, and the meansregulating its position will be adjusted in such a manner as to let inthe equilibrium state, a portion of the beam impinge on the luminescentscreen and give there rise to a spot marking the counting result whichcould be read on a scale associated with the front end of the tube.

By connecting the targets through the tube walls, to suitable exteriorcircuits, it would be possible to use it as a step by step distributorof any nature, which can be designed namely to illuminate successivelyglow-discharge indicator lamps, or which can act as a calling selectortriggering suitable relays for telephone or similar purposes; by usingin the like manner only one of the whole set of targets, it would bepossible to demultiply the frequency of the incoming signals.

For a better understanding of the invention reference may be had to theaccompanying drawings forming a part of this invention, wherein:

Figure 1 is a perspective schematic view of the cathode ray tubedistributor and of its associated operating cir cuits, according to thisinvention;

Figure 2 is a more detailed schematic view of the target arrangement inthis tube;

Figure 3 is a wiring diagram of a counting system comprising two seriesconnected tubes;

Figure 4 is a schematic plan view of the target arrangement of anembodiment of this invention for difier ential counting;

Figure 5 is a more detailed schematic view of the said embodimentshowing the starting target arrangement;

Figure 6 is a schematic plan view of a modification of the targetarrangement of Figure 4, designed for the series setting as representedon Figure 3;

Figure 7 is a detailed perspective view of a complete counter tuberealized according to Figures 1 and 2, the envelope of the tube beingrepresented in a longitudinal cross-section; and,

Figure 8 shows an electrical diagram of operating characteristics ofsuch a tube with practical data given by way of example.

Referring more particularly to the drawing wherein similar referencecharacters designate corresponding parts throughout, there is shown, inFigure 1, a vacuum tight envelope 1, containing an electron gun 2, ananode 19 producing a beam 3, and directing it along a reference axiswhich coincides with the tube axis, a deflecting set 4 comprising aplurality of plates producing the electrostatical regulation field, anadditional deflecting system comprising two cylindrical coaxialelectrodes 5 and 5' producing the commutating field and a set of targetssuch as 6 and 10, put against the luminescent screen 7, or situated nearand opposite it, inside of the tube. The first deflecting systemcomprises several plates such as 8 and 9, the number of which is equalto the number of targets. To simplify the drawing, there were shown onlytwo plates connected to the targets 6 and 10 by means of conductors 11and 12.

The targets are distributed in a regular way around the tube axis whichcoincides with the gun axis and they are given a band shape and asymmetrical disposition as shown more clearly in Figure 2; these bandsextend towards the periphery of the tube in the direction which isopposite to that of the beam movement, and in such a manner that theexterior end of each of them, such as 13 of the band 6, is situated onthe radius 14 crossing the interior end 15 of the preceding one.Besides, one of the targets, 6 of Figure 1, is connected electrically bymeans of a strip 16 to a central target 21 disposed on the axis of thetube.

Each target-plate arrangement is connected through a particularresistance to the negative pole of a common biasing voltage supply 18,which, as it will be explained later, is necessary to secure theoperation of a tube using a secondary emission effect. There have beenshown only a resistance 17 associated to the plate 8 and a resistance17' connected to the plate 9. The positive pole of the said source 18 isconnected to the anode 19 of the tube, which is grounded as usual. Oneof these deflector-target sets, 8-6 on Figure 1, is connected to theterminal 20 used for a series system as will be described later inconnection with the Figure 3. The gun 2 comprises, as usual in a cathoderay tube, an emitting cathode and a controlling cylinder. A source ofthe anode voltage E is connected between the filament and the ground.One of the hollow cylinders 5 is connected to the terminal I1 to whichare applied the incoming pulses. The other cylinder 5', in order to fixits potential, is connected to the anode, to which is also connected aconcentrical conducting layer 24, deposited on the inside of the tubewall. Any suitable conducting means F is used to fix the potential ofthe screen and to connect it by means of a conductor g to the anode.

This apparatus operates in a following manner: nor mally, the electronbeam follows the tube axis and hits the central target 21 forming a partof the target 6. As, owing to the biasing battery 18, the potential ofthis target is negative in respect to that of the anode, it emitssecondary electrons, acquiring so a certain positive charge which istransmitted, through the connector 11, to the plate 8. The latter pullsup the beam and the impact spot of it will then glide radially upwardsalong the length of the strip 16. The beam takes an equilibrium positionshown at 23 in Figure 1, and remains there on the target 6. Thisequilibrium position is fixed by the potential developed across theresistance 17 by the secondary emission current. The conditions andexperimental data of these operation phenomenas are represented in amore clear and detailed manner in Figure 8, the description of whichwill be given later. The said current is collected by the conductinglayer 24 deposited on the wall near the target arrangement. In somecases, this electrode may be omitted, and the anode 19 will then begiven the function of a secondary emission collector.

According to one feature of the invention, the magnitude of thesecondary emission is adjusted so that in its equilibrium position, thebeam hits partially the target and that another part of the beam sectionimpinges on the screen 7 giving there rise to a luminous spot indicatingthe beam position. This can be done by adjusting the beam speed, or theleakage resistances, or by choosing an appropriate secondary emissionrate or other suitable regulations.

Thus, the starting conditions are characterized by the followingparticularities: the beam pencil takes a fixed position and remainsthere; a luminous spot 25 marks this position; a positive potential inrespect to the common feeding potential of the targets, appears on theterminal 20 connected to the plate 8 and the target 6.

The commutating operation due to the incoming pulses, will be betterunderstood by means of Figure 2, representing the target and platearrangement, viewed through the tube end wall and in which, to simplifythe drawing, the central target 21 and its radial strip 16 are omitted.

First, it is supposed that the arriving pulses are short and havesubstantially constant durations and amplitudes, and that moreover theyare positive. These conditions may be easily fulfilled by any suitablewell known levelling and duration controlling amplifier and similardevice used normally in electroniccounters of the known types.

At rest, the beam passes through the hollow central commutating,cylinder 5', and as soon as the apparatus begins to work, the beamleaves this position and crosses the annular spacing between thecylinders.55". A positive pulse applied to the terminal I1, will buildup a radial field between these cylinders directed towards the exteriorone, and this additional field will increase momentan'ly substantiallythe radial deflection of the beam which will leave the spot 23 and getthe next target 26 hit in 27. In this new position, of a very shorttransitory character due to the reduced length of the pulse, the beamproduces a secondary emission from the exterior end of this target andthe deflection plate 28 connected to it through conductor 29, will get apositive potential. The regulation field is then commutated, and passesthrough the radial plane of the plate 28. The latter will attract on itsturn the beam towards the exterior of the tube, and at the same timewill submit it to a movement of lateral translation. As the attractioneifect of the plate 8 which is losing its positive charge, decreasesrapidly, the beam will glide, under the combining effect of all thesesuperposed forces, along the target 26. and will occupy finally a newequilibrium position 30 similar to the position 23 on the precedingtarget. As before, only a part of the beam section will hit the targetsurface, the remainder of it will reach the screen and let appeartherein a luminous spot 31 marking its new position corresponding to thefirst pulse.

When a new pulse is applied to the exterior commutating deflector 5, thesame operating phenomena will take place again and the beam will reachthe following target 32 and rest there until the arrival of a thirdpulse, producing so on the screen a spot marking the recording of thesecond pulse and so on for successively all targets.

When the beam hits any one of the targets, a positive potential appearson the deflecting plate connected thereto. This potential change may beused in a different way, for example to trigger control relays of acalculating machine. In the case of the counter as illustrated in thepresent invention, this eifect is used to control a second tubeconnected in series to the first, as represented in the Figure 3, wherethe terminal 20 connected to the plate 8target 6 set, controls thecommutating system of a second tube 40 made according to the invention.Each tube has ten targets and counts therefore ten pulses, the resultbeing read in the scale 34, impressed on a ring band 34 surrounding thescreen; the result marking figures may be of course impressed directlyon the tube bottom or projected on the latter. The mark corresponds tothe equilibrium position 23 on the target 6, as shown in Figure 2. Themark 1 corresponds to the target 26, and finally the mark 9 to the tenthtarget preceding the target 6.

The incoming signalsare applied to the outer deflecting cylinder througha series condenser 36,.a resistance 37 links this cylinder to the anode.By giving to thecircuit 36-37 a feeble time constant, it becomespossible to transform even large pulses into short ones necessary tooperate the counting tube.

As it was described before, the single terminal 2%} is connected to thetarget 6 on which the beam impinges when no pulses have been applied, orwhen after recording ten pulses, the beam has swept an entire circle.The outer cylinder 38 of the commutating element 39 belonging to thesecond tube 4t designated to count groups of ten similar to the unitstube 33, is connected to this terminal 20 through a differentiallyacting time constant circuit comprising a condenser 41 and a resistance42 connccted to the anode 43. The increase of potential of the terminal20 at the moment when the beam hits the target 6 gives then rise to ashort positive triggering pulse 44 controlling the movement of thesecond counter ill beam.

When, on the contrary, the beamfleaves the target 6,

"when it is commutated to the next one 26, the potential of the terminal20 will decrease, and this will give rise on the terminal of the circuit41-42 to a negative parasite pulse 45. But the latter does not introduceany disturbing effect, as it will displace the beam inwardly towards thetube axis without touching any other target. Furthermore, this inwardmovement will bring the entire sect-ion of the beam on the targetsurface, and therefore increase quantity of electrons hitting it. Thecorresponding sudden increase of the positive charge of the deflectingplate connected to this target, will try to reduce and to nullify thisparasite displacement.

Several other similar tubes recording groups of hundreds, thou-sands,etc., can be connected in the similar manner, in order to increase thecounting capacity of the apparatus.

The embodiment represented on the Figure 4 is intended for adding pulsesof different natures and more particularly pulses of opposite signs.This dilferential counter is derived from the described one, by simplygiv ing to the targets a particular form and disposition. They are asbefore in the band form of the same size and shape and arrangedobliquely in a plane transverse to the tube axis; but in thismodification, one band overlaps the preceding one by about a half of itslength, in such a manner that a radius such as 46 crosses successivelythe end of the target 47 near the tube axis, the middle of the nexttarget 48 and finally the farthest end of the target 49. Each target isconnected, as before, to a particular regulating deflecting plate, i. e.the target 47 is connected to the plate Stl, the target 48 to the plate51 and the target 49 to the plate 52, and so on. These plates are nowarranged so as to deflect the beam in a radial plane which crosses thecentral part of the corresponding targets. For example, in itsequilibrium position the beam will hit the target 48 at the point 53 inthe radial plane of the plate 51. In order to simplify the drawing therehas not been shown the starting target arrangement.

If the beam impinges at a given moment on the target 48, and if acontrol pulse to be recorded, of a suitable amplitude and length,deflects the beam radially outwards, as it was described in connectionwith the preceding figures, the beam will reach the next target 49 atthe point 54, will then glide along it and finally get an equilibriumposition at 55. But if the control pulse is of such a nature that itdeflects the beam inwardly towards the axis, the beam will reach thepreceding plate 47 at 56, and will then glide towards 57 under thedeviating control of the plate 50. Therefore, in order to secure adifferential distribution of pulses, the latter must, according to theirsign, or their source of supply give rise to commutating deflections ofopposite senses, and this will be secured in the following manner: if itis wanted to sum up algebraically a certain number of positive andnegative pulses, it is only necessary to apply all them to the sameinput terminal of the tube such as the ll of the Figure 1, leading tothe exterior cylindrical deflector 5. Then the positive pulses willdeflect the beam outwardly and the negative inwardly thus letting thebeam return to-the end of the preceding target.

If, on the contrary, it is wanted to realize a difference between twoseries of pulses, all of the same sign, but supplied for instance fromdifferent sources, then the pulses of one of the series will be appliedas before to the terminal I1 of the Figure 1, and the pulses of thesecond one to the terminal is connected by a dashed line to the interiorcommutating cylinder 5' where they will give rise to an opposite radialdeflection action.

It is clear that the positive and negative pulses or the pulses of thetwo series must present substantially the same amplitude which will beadjusted suitably according to the operating characteristics of thetube, in order that the radial deflection amplitudes be sufficient todrive the beam from one target to the other, but not strong enough tolet it overshoot this target and reach thethird one. If these conditionsare fulfilled, the distributor will act exactly as a counter marking thealgebraic sum of the pulses, but not the sum of their amplitudes.

If it is supposed that the target 48 forms the origin of the counting,and that the spot 53 marks the zero, then, on the contrary to thecounter of the Figure 1, in this differential embodiment, the startingauxiliary electrode 59 must be connected, by a conductor 60, to thefollowing target 49, as it is represented on the Figure This elec trode59 is arranged radially in the sense of the deviation imparted to thebeam by the plate 52, connected to the target 49, but it ends slightlybefore the target 48 and is therefore insulated therefrom. As theequilibrium position of the beam is out of the electrode 59 edge, thebeam after it has travelled along it, continues its radial movement andreaches the interior end 61 of the target 48. At this moment, thesecondary emission from the latter produces a change of potential of thecorresponding plate 51, whereas the deflecting charge of the plate 52disappears owing to the stopping of the secondary emission of the target49. The beam is then attracted laterally towards its starting position53 on the target 48. If the starting electrode was connected to theorigin target 48, the initially secondary emission would bring the beamin the contact with the intermediate target 47 and then it would bepushed the length of the latter until the middle point corresponding tothe equilibrium position.

In the case of a series system comprising several differential countingtubes as described, forming decades counter, it is not sufficient, as inthe diagram of the Figure 3, to use the potential acquired by the origintarget 48 to trigger the following tube. In this case it becomesnecessary to make either advance or move backwards this commutatoraccording to the polarity or the origin of the controlling pulse whichmay bring the beam on the origin target or let it leave it. That is if,for example, the first tube or units tube is commutated fro-m theposition 9 to the position 0, the second tube marking the group of tensmust advance from 0 to l, but if the first returns back, from 0 to 9, itmust trigger back the tube of tens from the posit-ion 1 to the position0.

The Figure 6 represents an embodiment of the invention permitting tocontrol in an appropriate sense the second decade counter, and using forthis purpose two auxiliary targets electrodes 62 and 63. When thecounter is in the position 9 the beam spot occupies the position 57 onthe target 47. If, at this state, the incoming pulse is to be counted ina positive sense, that is if the tube has to get the position 0 and mustthen let advance by an unity the following decade counter, this pulseproduces a radial deflection of the beam directed outwards, from theposition 57 to the position 64 in which it hits entirely the auxiliaryelectrode 62. The latter takes a transitory positive charge which can betransmitted in the form of a short pulse, to the commutating electrodeof the following tube, to let it advance by one I unity.

At the end of the control pulse applied to the first counter tube, thebeam deflection will decrease and the spot will then leave the electrode62 and reach the target 48 and glide along it until it will get itsequilibrium position 53.

If, on the contrary, the first tube is at the position 0 and the controlpulse is to be counted in a negative sense, the second auxiliaryelectrode 63 will then be used. The spot being at 53, this control pulsewill direct it radially inwardly towards the tube axis and it willtherefore hit during a short time the target 63, which will acquire afugitive positive charge. The latter will be transmitted to the suitablecommutating electrode of the following tube, making it go back by oneunity. At the end of the control pulse, the spot leaves the electrode 63and meets the preceding target 47 at 56 and glides therefrom to itsequilibrium position 57.

It can be observed that during its deflection caused by the controlpulse, the beam crosses the next target before reaching the auxiliaryelectrode. But it is easy to adjust the operating characteristics of thetube in such a manner as to reduce greatly the time of this crossing andto render negligible the secondary emission and its effect. On thecontrary, duringits back travel, the beam returns much more 'slowly toits normal equilibrium position and the deflecting potential created atthe corresponding plate enters immediately into action and prevents thebeam from overshooting the band target it had met.

To bring the counters according the invention to a zero position, at theend of a counting operation, it would be sufiicient to stop simply thebeam of all commutator tubes, such as by applying a negative pulse of asuitable very short duration to their control cylinders. The targetsunder action at this moment, will lose their charges and the deflectionfields would disappear. If then the tube beam is started again, it willimpinge axially on the central starting electrode and after glidingautomatically along the origin target, reach its zero position asdescribed above.

The complete distributing and simultaneously counting tube representedon the Figure 7 comprises inside the tight envelope 1 of glass or otherinsulating material, a stem 81 surrounding by a metal collar 83supporting, by means of a flat strips and 82, the electron gun 2comprising an emitting filament and a surrounding con trol cylinder.Their lead-in conductors are embedded in the said stem. The anode 74 isfixed to an annular piece of mica 74 partly sectioned so as to show theinner electrodes. Four similar flat insulating supporting rings 70, 71,72,.and 72, are mounted inside the tube and fixed thereto by means ofclasps 78 represented only in combination with the ring 70. These ringsare crossed by a series of metal rods 11, 12, arranged round the tubeaxis and forming with the rings a rigid fixture which can be assembledout of the tube and slipped into it. The pair of rings 7273 carries theregulating deflecting plates 89, fixed thereto by means of their flangedends 8 respectively 9'. Each of them is connected through a conductinglayer not designated on the ring to its corresponding rod. Each rodsupports a particular leakage-potential fixing resistance 17-17', whichend in an annular conducting deposit 79 forming a common point, lead outthrough a wire crossing the stem. The ring 71 carries the outercommutating cylindric electrode 5 by means of riveted straps 75, theinner tubing 5 being fixed in the same manner by means of straps 76. Twoindependent wires lead them to the stem. The band shaped metallictargets 6, 26, 10 (the others being omitted for the sake of clearness)are riveted to the side of the ring facing the screen '7 and are soarranged that all their active portions, that is those hit by the beam,protrude into the circular opening of the ring. During the commutatingperiod the beam would strike the screen but as this period is veryshort, its trace would even not be noticeable. These target strips canalso be fixed to the surface of the ring facing the gun, letting merelytheir interior tips penetrate into the ring opening, allowing thus thebeam to strike the screen in its equilibrium position. Then during thecommutating period the beam would charge somewhat the insulating ringsurface, but this phenomena would not be practically noticeable, andmoreover, the natural leakage effect of the ring and its surroundingmedium, would secure the necessary equilibrium effect. Conductingdeposits such as 77 on the screen side of the ring, connect each targetto a particular rod 11, 12, leading to a corresponding deflecting plate.A circular conducting layer 24 on the inside wall of the tube formed byspraying a conducting substance such as graphite solution, is connectedthrough the wire 8 to a lead in conductor in the tube stem 81, andmoreover to the fluorescent screen of a conducting or semi-conductingtype, through a conducting layer 3, such as are commonly employed in thecathode ray tube practice. The targets are made of a suitable materialof a high secondary ernission power; nickel can be employed eventuallycoated with a barium or a strontium oxide or other alkali metalcompound. The counting result marks are traced directly on the outsideof the tube bottom.

In the Figure 8 representing an equilibrium state of the tube operation,the different arrows show the conventional direction of the current flowwhich is opposite to the direction of the electron movement. Theelectron beam of 0.15 milliampere, chosen by way of example, isfurnished by the anode supply E of 1000 volts. This voltage can be fixedrelatively low, as neither sharp focusing eifect nor high brillancy ofthe spot are needed; on the other hand, a low accelerating voltageincreases the sensibility of the beam deflection and protects. thescreen against burning. After its deflection by the transverse field ofthe plate 8, the beam gets to the plane of the target 6 where it isdivided into two parts: the one of 0.10 ma. intensity follows the sametrajectory, impinges on the screen giving there rise to a luminous spotand returns to the plus pole of the anode battery through. the secondaryemission eflect of the screen and the leakage path comprising the layer24 as it is usually the case in the normal cathode ray tubes. The otherfraction of the beam of 0.05 ma. intensity hits the target giving riseto a secondary emission current of 0.25 ma., by supposing a ratio of 5.This emission, owing to the battery 18 biasing the target negatively inrespect to the anode, is collected by the layer 24 put to the anode, andreturns to the positive pole of the anode supply through the latter. Thetotal current leaving the layer 24 is therefore of 0.35 ma. The targetreceives a current of 0.05 ma. and supplies current of 0.25 ma. andtheir difference is compensated by a current of 0.2 ma. furnished by thebiasing battery 18. This current develops on the leakage resistance 17of 100,000 ohms, a potential difference of 20 volts appearing betweenthe active plate 8 and the others, determining the deflection fielddirected towards the first one. As it was represented on the Figure 2,the beam position and section were so regulated that its spot overshotthe outer rim of the target. Thus any operating conditions variation,such as an accidentally change of secondary emission, would beautomatically compensated by a more or less deep penetration of the beaminto the target section, and this floating characteristic of the beamspot would maintain it on the target surface during the commutatingperiod and stabilize it in its equilibrium position. On the other hand,this self-regulation of the equilibrium condition is enhanced by thefact that the secondary emission is a function of the potentialdifference between the target and the collecting layer and that, inthese conditions, the said potential, the deflecting field and thesecondary current are interacting to secure the said self regulatingetfect.

It must be well understood that this invention is not limited to theparticular form and disposition of targets or deflecting electrodes asrepresented on the drawings and described above. The first can be givenany other shape and mutual arrangement provided that a radial suddenpush or pull will let the beam leave one target and reach the next one,and that, under the action of the operating field, the beam glides alongthe target until it reaches a new equilibrium position on it.

Instead of the embodiment shown on the Figure 7, the targets may berealized by depositing a layer of suitable material on the bottom of thetube supporting the screen and then the target-plate connectors may bemade by means of exterior wires; the screen may also be supported by themica ring carrying the target strips. The regulating resistances 17 maybe made by coating the inner wall of the tube, or assembled out of thetube and provided with necessary lead-in wires. Instead of using afluorescent screen for illuminating and reading the counting results,the targets may be provided with connectors crossing the tube walls andleading out their charges to signal indicators in the case of counting,or

relays or other suitable responsive devices in the case of using thetube simply as distributor. V

The commutating counting devices according to the-invention are verysimple to build, operate reliably and moreover are very sensitive. Theymark at any instant the total of the algebraic addition of receivedpulses according to their polarity, and also the difference between twoseries ofpulses. Moreover, they secure a high speed operation, i. e.they can record very short pulses and can therefore be controlled bypulses arriving at a high rate. If C is the total capacity of thetarget, of its deflecting plate and all connectors, if R is theresistance connecting the plate to the bias battery, such as 17 (Fig.1), and r is the resistance of the secondary emission path, the rate ofthe counting speed is fixed by the timeconstants CR and Cr. By adjustingC to a 5 micromicrofarads, R to 100,000 ohms, and supposing that thesecondary emission current which determines the resistance r is of about0.25 milliarnpere, the said time constants will be of about 5/10microsecond, thus allowing a counting speed of about 2 million pulsesper second. This speed can be substantially increased by choosing a beamof a larger intensity and by reducing leakage resistance.

Besides, the cascade counter allows to add up a very' high number ofpulses with onlya relatively few tubes.. As each of them can recorduntil 10, it becomes possible to secure a counting power of 1.0 withonly 7 tubes con-- nected in series.

To get the same. result, it would be necessary with the: hitherto knownelectronic counting systems such as using binary multivibrators, to use5 of them for each decade recording, this increasing substantially thenumber of' tubes and of coupling, circuits, as like as the number ofvisual indicators associated herewith, whereas the tube of thisinvention fulfills simultaneously the counting and indicating functions.All leakage resistances 17 being situated inside the tube wall, thelengths of their circuits. can be reduced to minimum thus diminishingstill more the time constants and increasing the counting speed.

What is claimed is:

1. In an electric step by step type pulse distributor, a cathode raytube, means inside said tube for producing an electron beam and fordirecting said. beam along a predetermined reference axis, a pluralityof targets located inside the tube and around said axis for receivingthe beam, a plurality of deflecting means arranged around the said axisso as to deflect thebeam in different radial planes extending throughsaid axis and said targets, means to connect separately and directlyeach target to the corresponding deflecting means located in the sameradial plane, a supplementary starting target located in said ref erenceaxis, connected to one of said targets and independent means undercontrol of the incoming pulses to be distributed for acting upon thebeam so as to change the amplitude of its deflection imparted by theaforesaid deflecting means irrespective of the beam position.

2. In an electric step by step type pulse distributor, a cathode raytube, means inside said tube for producing an electron beam and fordirecting said beam along a predetermined reference axis, plurality ofelectrostatically deflecting means inside said tube and arrangedcircularly with respect to said axis so as to form a plurality of different radial deflecting planes passing through said axis, a plurality ofband shaped beam receiving targets distributed around said axis andlocated obliquely with respect thereto, in such space relationship tosaid deflecting means, that a radial plane drawn through each of thelatter cuts at least two targets, independent means to connect directlyeach one of said targets solely to the deflector situated in its plane,a supplementary, independent commutating deflector inside said tube, forproducing a radial electric field distributed uniformly around saidreferance axis, means for applying to said deflector the incomingpulses, a supplementary starting target located in said reference axis,connected to one of said targets and means associated with the targetsand controlled by the beam impact. 7

3. In an electric pulse counting apparatus, a cathode ray tube, acathode and an anode inside for producing an electron beam and directingsaid beam along the tube axis, a plurality of deflecting plates insidesaid tube and arranged circularly in respect to said axis, a pluralityof band shaped targets, of a material emitting a high ratio of secondaryelectrons distributed around said axis and located obliquely withrespect thereto in such space relationship to said plates that a radialplane drawn through any one of the deflecting plates cuts at least twotargets, independent means to connect separately and directly each oneof said targets to the plate situated in its plane, a supplementary,hollow commutating electrostatical deflector inside, said tube betweensaid targets and plates, for producing a radial field distributeduniformly around said axis, means to apply to said deflector theincoming pulses, a fluorescent screen associated with the targets, asupplementary starting target crossing said tube axis, connected to oneof said targets a particular leakage resistance leading from eachdeflecting plate to a common connection point, and a continuous biassource having a negative pole connected to said point and positive poleto said anode.

4. In an electric pulse counting apparatus, a cathode ray tube, meansinside said tube for producing an electric beam and for directing italong a predetermined reference axis, a plurality of electrostaticallydeflecting plates inside said tube arranged circularly with respect tosaid axis so as to form a plurality of different radial deflectingplanes'passing through said axis, a plurality of band shaped targets forreceiving the beam, located substantially in the same transverse planeand distributed regularly and obliquely with respect to said axis and insuch a manner that the outer end of one target overlaps in a radialdirection drawn from this axis, the inner end of the following target;independent means to connect separately and directly each of theaforesaid plates to the target the inner end of which is situated in theradial plane extending through said plate, a supplementary commutatingdeflector inside the tube between said plates and targets for producinga radial field distributed uniformly around said axis; means to applythe incoming pulses to said deflector, a fluorescent screen associatedwith the targets, a supplementary starting target located in saidreference axis, connected to one of said targets, a supply circuit forenergizing the tube, and a leakage resistance between each of saidplates and said circuit.

5. In an electric pulse counting apparatus of the differential type, acathode ray tube, means inside said tube for producing an electron beamand directing said beam along a predetermined reference axis, aplurality of deflecting plates inside said tube arranged circularly withrespect to said axis so as to form a plurality of different radialdeflecting planes passing through said axis, a plurality of targets forreceiving the beam, of a curved elongated band form located in the sameplane substantially perpendicularly to said axis, arranged symmetricallyand extending obliquely with respect to said axis, overlapping eachother and situated in such a space relationship to said deflectingplates that a radial plane passing through a plate cuts the outer end ofone target, the middle part of the intermediate one and the inner end ofa third target, independent means to connect separately and directlysaid plate to said intermediate target, a supplementary commutatingdeflector inside the tube between said plates and targets for producinga radial field distributed uniformly around said axis, means to apply tosaid deflector the incoming pulses, a fluorescent screen associated withthe targets, a supplementary starting target located in said referenceaxis, connected to one of said targets a supply circuit for energizingthe tube,

12 and a leakage resistance between each of said plates and saidcircuit.

6. Tube for counting purposes comprising an evacuated vessel andenclosed therein means for producing an electron beam and directing italong a tube axis, a plurality of deflecting plates arranged circularlyin respect to said axis so as to form a plurality of different radialdeflecting planes passing through said axis, a plurality of band shapedtargets of high secondary emission for receiving the beam distributedaround said axis and located substantially in the same transverse planeand distributed regularly and obliquely with respect to said axis and insuch a manner that the outer end of one target overlaps in a radialdirection drawn from this axis, the inner end of the following target,independent connectors for linkll'lg separately and directly each ofsaid plates to the target, the inner end of which is situated in theradial plane extending through said plate, and which is located on thesame side of the tube axis two hollow cylindrical coaxial electrodesspaced apart'and disposed concentrically with respect to said axisbetween said targets and plates, control lead-in conductors connected tosaid electrodes, a supplementary starting electrode located centrally insaid target plane, a radially extending conducting path connecting saidelectrode to the zero position target; and a fluorescent screenassociated with the targets.

7. Tube as claimed in 6, wherein the target, last struck by the beam, isled out by a particular conductor to an output terminal.

8. Tube as claimed in 6, wherein each deflecting plate is connected witha particular leakage resistance, said resistances terminating at acommon connecting point.

9. Tube for counting purposes comprising an evacuated vessel andenclosed therein, means for producing an electron beam and directingsaid beam along a tube axis, a plurality of deflecting plates arrangedcircularly with respect to said axis so as to form a plurality ofdifferent radial deflecting planes passing through said axis; aplurality of targets of high secondary emission for receiving the beamof a curved elongated band form located in the same plane substantiallyperpendicular to said axis, arranged symmetrically and extendingobliquely in respect to this axis, overlapping substantially each otherand situated in such a space relationship to said plates that a radialplane passing through a plate cuts the outer end of one target, themiddle part of the intermediate one and the inner end of the thirdtarget, independent connector for linking separately and directly saidplate to said intermediate target, located on the same side of the tubeaxis, two hollow coaxial cylindrical electrodes spaced apart anddisposed concentrically with respect to said axis between said targetsand plates, a supplementary starting target located centrally in saidtarget plane, a conducting path extending radially from said electrodetowards the Zero position target and connected to the following targetoverlapping it, and a fluorescent screen associated with the target.

10. Tube as claimed in 9, comprising two additional targets situated,respectively, near the outer end of one of its targets and the inner endof the following target overlapped by the first one.

11. Electric pulse counting system comprising at least two seriesconnected tubes as claimed in claim 7, a resultindicating scaleassociated with each of said tubes, an output terminal connected to onepredetermined platetarget set of the first tube, an input terminalconnected to the commutating cylindrical deflector of the second tube,and a coupling circuit having a predetermined time constant between saidterminals.

12. In an electric pulse step by step distributor, a cathode ray tube,means inside said tube for producing a pencil-like electron beam, aplurality of targets for receiving said beam located inside said tube, aplurality of beam deflecting means, each determining a particulardeflection plane, to each target corresponding a particular deflector,both being situated in the same deflection plane, an independentconnector directly linking each target to its corresponding deflector, asupplementary starting target located in the trajectory of theundefleeted beam and linked to one of said targets, a supply circuit, anindependent resistance to link separately each target deflector set tosaid supply circuit, and independent means controlled by the incomingpulses to be distributed, for acting upon said beam so as to commutateit from one target to another.

13. In an electric pulse counting apparatus, a cathode ray tubecomprising inside thereof means for producing an electron beam aplurality of targets for receiving said beam, each determining anequilibrium position, a plurality of beam deflecting plates, eachdetermining a particular deflection plane, an independent directconnection between each deflecting plate and the target located in itsdeflection plane, a supplementary starting target located in thetrajectory of the undeflected beam and linked to one of said targets, anexternal supply circuit for energizing said tube, an independentresistance to link separately each target-deflector set to said supplycircuit, an input circuit for receiving the incoming pulses to becounted, and a supplemental hollow deflectingcommutating system insidethe tube, located between said targets and plates, controlled by saidcircuit and arranged so as to create a supplementary electrostatic fieldsimultaneously in all said deflection planes.

l4. Tube for counting purposes comprising an evacuated vessel, andinside thereof means for producing an electron beam and directing saidbeam along the tube axis, a plurality of deflecting plates arrangedcircularly with respect to said axis, each determining a particularradial deflection plane, a beam receiving target of high secondaryemission in each of said planes, an independent direct feedbackconnection between each of said deflectors and the target located in itsplane on the same side of the tube axis, an independent potentialstabilizing connection for each target-deflector set; a hollow beamcommutating system for creating a supplementary electric fielddistributed around said axis, and a starting means actuated by the beamin its undeflected position and drawing the beam to the zero positiontarget.

15. An electronic counter tube comprising an envelope, an electron gunin said envelope for generating an electron beam, a plurality ofsubstantially coplanar anodes positioned in the path of said beam, aplurality of defleeting plates in said envelope equal to the number ofanodes therein, means simultaneously interconnecting said anodes withtheir corresponding deflecting plates and the electron gun to cause saidbeam to have a stable position on whichever of said anodes the beam maybe received on in the absence of additional beam deflection forces whensaid anodes are energized, said anodes being shaped to have more thanone anode intersected by radial movement of said beam; a ring shapedcontrol electrode passing around all positions of the beam, means forfeeding energizing pulses to said ring and thereby effective to movesaid beam radially from one anode to the next in either direction.

References (Iited in the file of this patent UNITED STATES PATENTS2,200,745 Heymann May 14, 1940 2,201,323 Shelby May 21, 1940 2,233,275Wolff Feb. 25, 1941 2,365,476 Knoop et a]. Dec. 19, 1944 2,414,444Busignies Jan. 21, 1947 2,447,233 Chatterjea et al Aug. 17, 19482,488,452 Overbeek Nov. 15, 1949 2,597,360 Moon May 20, 1952

